EN
20/44
Fig. 9: Tightening the union nut with a spanner
INSTALLATION OF OUTLET TUBES
Tubes are usually assembled with tube fittings. Assembly
starts inserting the tube completely into the fitting. Then
screw the union nut by hand and tighten the nut with a
spanner (1 1/4 turns). Please take care to follow the manu-
facturers instructions and the compatibility of gas type/
pressure with materials.
EXTERNAL GAS PURGING FMD 500/502-21
Use corrosive, flammable or oxidizing gases and f. e. the
cylinder pressure regulator FMD 500/502-21, you have to
purge the unit with external gas before installation, startup
end ending operation.
Cylinder pressure regulators with external gas purging
make it possible to: dry the fitting and/or remove damp
atmospheric air which may have entered the station be-
fore start-up or when changing cylinders, purge out tox-
ic, corrosive or pyrophoric gases from the fitting before
changing cylinders and before ending operation.
Dry purging gas N2 or Ar 5.0 of 4 - 10 bar is required for successful purging..
1.
Check that purging lines (7) and exhaust lines (5) are connected correctly.
2.
Close all valves of the fitting (handle at right angles to pipe).
3.
Turn the handwheel of the pressure regulator (2) as far as possible anticlockwise - through passage is
thus closed.
4.
Open the purge gas inlet valve (7).
5.
Open the pressure regulator (2) partially by turning the handwheel approx. two revolutions clockwise.
6.
Close the purge gas inlet valve (7). Allow the purging gas which has now flowed into the pressure regula-
tor to remain there for a few seconds.
7.
Open the process gas outlet valve (5) briefly and allow the purging gas to escape. Then close the process
gas outlet valve (5) again immediately.
8.
Repeat steps 4., 6. and 7. between five and seven times.
9.
Close all valves of the station. Close the pressure regulator (2) completely by turning the handwheel
anticlockwise.
6.2. LINE AND SUPPLY PRESSURE REGULATORS
PREPARATION
Release the gas pressure, purge if necessary with inert gas (see VBG 50). Then open the pipelines with spe-
cial tools, avoiding turnings. Make sure the lines and connection pieces are in clean, impeccable condition.
CONNECTION
Line and supply pressure regulators are usually delivered with tube fittings. Installation requires complete
insertion of the pipeline into the connection. Then screw on the union nut by hand and tighten it (1 1/4 turns)
with an open-end spanner.
START-UP
When connecting or changing cylinders containing toxic or corrosive gases, appropriate personal protection
measures must be taken (respiratory protection, eye protection and protective clothing). Observe the MAK
values (maximum workplace concentration value; see Technical norms for dangerous substances, TGRS
900) and have the correct respiratory protection filters at hand.
Before switching on the pressure device ensure that no-one can be put in a situation of danger by starting
up the pressure device.
Use only pressure device with external gas purging when working with toxic, corrosive or pyrophoric gases.
PREPARATION
Take care that process and purge gas lines are connected gas tight to the appropriate in- and outlets. Turn
the handwheel of the regulator counter-clockwise, thereby closing the valve gate. Close all valves.
LEAKAGE TEST
Open the cylinder valve and close immediately. Spray leakage test spray over the cylinder connection. If
there results a formation of bubbles, tighten the cylinder connection until the formation of bubbles stops. If
seals have been changed, repeat the leakage test after 24 hours respective tighten the cylinder connection
again.
EXTRACTING PROCESS GAS
Slowly open the cylinder valve. Watch the inlet pressure gauge. Set the desired outlet pressure by turning the
regulator handwheel clockwise. Set the desired flow volume on the metering valve (if applicable).
+
+
7.
Содержание 200
Страница 43: ......